A major, late 6-kilobase (6-kb) mRNA mapping in the large unique region of herpes simplex virus type 1 (HSV-1) was characterized by using two recombinant DNA clones, one containing EcoRI fragment G (0.190 to 0.30 map units) in X.

Recombinant bacteriophage lambda clones from a cat genomic library derived from placental DNA of a specific pathogen-free cat were screened to identify endogenous feline leukemia virus (FeLV) sequences. Restriction endonuclease mapping of four different clones indicates that there are a number of similarities among them, notably the presence of a 6.0- to 6.4-kilobase pair (kbp) EcoRI hybridizing fragment containing portions of sequences homologous to the gag, pol, env, and long terminal repeat-like elements of the infectious FeLV. The endogenous FeLV sequences isolated are approximately 4 kbp in length and are significantly shorter than the cloned infectious FeLV isolates, which are 8.5 to 8.7 kbp in length. The endogenous elements have 3.3- to 3.6-kbp deletions in the gag-pol region and approximately 0.7- to 1.0-kbp deletions in the env region. These deletions would render them incapable of encoding an infectious virus and may therefore be related to the non-inducibility of FeLV from uninfected cat cells and the subgenomic expression of these endogenous sequences in placental tissue. It appears that there is conservation in the ordering of restriction sites previously reported in the proviruses of the infectious FeLVs in sequences corresponding to the pol and env boundary as well as the region spanning the env gene of the endogenous clones, whereas a greater divergence occurs among restriction sites mapped to the gag and part of the pol regions of the infectious FeLV. Such deleted, FeLV-related subsets of DNA sequences could have originated either by germ-line integration of a complete ecotropic virus followed by deletion, or by integration of a preexisting, defective, deleted variant of the infectious virus.

Total cellular polyadenylated RNA from a variety of fresh human lymphoma and leukemia cells, characterized by histopathology and certain cell surface markers, was analyzed for the expression of three distinct cellular oncogenes (c-onc genes), c-erbB, c-myc and c-myb by dot-blot hybridization assays. Probes used were molecularly cloned DNA containing the respective oncogene sequence of avian erythroblastosis virus, myelocytomatosis virus (MC29) and myeloblastosis virus. All lymphoma-leukemia cells irrespective of B, T or non-B/non-T lymphocyte lineage expressed the c-erbB locus. This gene was also found to be active in normal peripheral blood lymphocytes and lymphocytes from lymph nodes showing reactive hyperplasia. This observation suggested that c-erbB might be normally involved in cell growth functions since it was not unique to hematopoietic malignancies. In contrast to c-erbB, elevated expressions of c-myc or c-myb were detected in certain neoplasms of B-lymphocytes and some other lymphoproliferative disorders as compared to the majority of the samples tested which showed either low or undetectable levels of these transcripts. An examination of B-cell lymphomas and leukemias in which the majority of the cellular populations expressed either Kappa or lambda surface lg light chain molecules revealed variations in the levels of c-onc transcripts within a morphologic and immunologic subtype. These findings support the notion that, in general, genetic heterogeneity exists in groups of hematopoietic proliferations defined by conventional histopathologic and immunologic criteria. Although with the majority of the specimens there was no obvious correlation between the morphologic cell type of lymphoma/leukemia and the c-onc RNA levels, interestingly two of the three samples diagnosed as chronic lymphocytic leukemia, B-cell type, showed considerably increased transcription of the c-myc gene relative to the other B-cell neoplasms. Thus a class of differentiated B-cell leukemia has been identified in which the molecular mechanisms which affect c-myc gene expression can now be investigated.

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Expression of endogenous retrovirus genes and two different cellular oncogenes (c-onc genes) was examined at the transcriptional level in a variety of normal and lymphoma/leukemia tissues of the domestic cat. The two oncogenes, c-myb(re1ated to avian myeloblastosis virus) and c-myc(re1ated to avian myelocytomatosis virus) were selected for their association with the induction of hematopoietic malignancies, when present in the transforming retroviruses. Tissue-specific expression of endogenous feline leukemia virus (FeLV)-related genes was detected in cellular subpopulations of the cat placenta by in situ method of hybridization. Gel blotting analysis of placental poly(A)-selected RNA revealed that the FeLV-related RNA species were primarily subgenomic, representing the env gene region of the endogenous provirus elements. Like the endogenous retrovirus genes, c-myb and c-myc loci ofthe cat genomic DNA were also transcribed at differential levels in normal tissues of the cat. Dot-blot hybridization analysis showed that the expression of these two oncogenes was linked to growth and development as it varied with the gestational age of the fetus and from fetal to adult tissues. Among the major hematopoietic organs, spleen and bone marrow contained both c-myb and c-myc transcripts, while thymus preferentially expressed the c-mvb gene. In contrast to the low level of c-myc expression in fetal thymus tissues, enhanced c-myc expression was detected in all five thymomas tested and also in several other neoplasms including two granulocytic leukemias. The feline c-mvb gene was not very active in granulocytic leukemias or in three of the five thymomas. RNA gel blotting analysis of poly(A)-selected RNA of a thymoma and its lymph node metastasis showed identical pattern of c-myc transcripts.

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Recommender systems are in recent past becoming more notable in the age of swift evolution of the information technology ensuring e-commerce users' suitable items. In recent years, various thread-based and trust based approaches have been proposed, which improve the precision and recall of recommendation to certain extent. However, these approaches are less accurate than expected when users' preferences evolve over time and when several aspects of the users are involved. To solve these problems, we propose a novel recommendation method called, Soft Cosine Gradient and Gaussian Joint Probability (SCG-GJP) for Online Social Networks (OSN). Specifically, the Local Soft Cosine Clique Clustering (LSCCC) is first used to identify good candidate items to be recommended. Second, using adjacency matrix factorization, probable past preference of individual user and overall preference of whole community is formed to reduce the problem of mean absolute error. Again, the obtained matrix is trained through the stochastic function gradient to rank the most suitable candidates. Finally, Gaussian Mixture Joint Probability Postfiltering model is proposed to provide useful recommendations. The experiments are executed with real-world dataset (DS) and compared with the conventional recommendation methods. Experimental results demonstrate that the SCG-GJP obtains higher accuracy, and lesser error as well as complexity.